Question

Kidney beans are soaked overnight before cooking.
(a) What is the observation you find after soaking?
(b) Name the phenomenon involved in the above observation. Explain the reason.
(c) Do you find the same change when a raw egg is placed in water? Justify that.

Answer 1

(a) On soaking overnight, kidney beans become swollen.
(b) The phenomenon that happens here is Endosmosis. The cells of the kidney beans are covered by a porous cell wall and a plasma membrane. Water enters the cells of the kidney beans as the cell sap has higher concentration. Thus, endosmosis takes place and the beans become swollen and palatable after cooking.
(c) A raw egg does not swell if kept in water as the material of the shell is impermeable to water.